Respirators (also referred to as "filtering face masks") are worn over the breathing passages of a person for two common purposes: (1) to prevent impurities or contaminants from entering the wearer's breathing track; and (2) to protect others from being exposed to pathogens and other contaminants exhaled by the wearer. In the first situation, the respirator is worn in an environment where the air contains particles harmful to the wearer, for example, in an auto body shop. In the second situation, the respirator is worn in an environment where there is a high risk of infection, for example, in an operating room.
To accomplish either of the above-stated purposes, the respirator must be able to maintain a snug fit to the wearer's face. Known respirators can, for the most part, match the contour of a person's face over the cheeks and chin. In the nose region, however, there is a radical change in contour, which makes it difficult to achieve a snug fit over that portion of the wearer's face. The failure to obtain a snug fit allows air to enter or exit the interior of the respirator without passing through the filter media. When inhaled and exhaled air is not filtered, contaminants may enter the wearer's breathing track or others may be exposed to contaminants exhaled by the wearer. In addition, the wearer's eyeglasses can become fogged by exhaled air that escapes from the interior of the respirator over the nose region, making visibility more troublesome to the wearer.
Nose clips are commonly used on respirators to achieve a snug fit over the nose of the wearer. Conventional nose clips are in the form of malleable, dead soft, linear, strips of aluminum--see, for example, U.S. Pat. Nos. 5,307,796, 4,600,002, 3,603,315; see also U.K. Patent Application GB 2,103,491 A. Conventional nose clips have provided a snug fit over the nose of the wearer, but the fit frequently has been obtained at the expense of restricting flow through the wearer's nasal passages. In addition, conventional nose clips are known to exert a clamping pressure on the wearer's nose and/or cheekbone, and this clamping pressure also can cause discomfort. Other nose clips have been disclosed in the art--see, for example, U.S. Pat. Nos. 2,153,437 and 2,572,254. These nose clips have the drawback of not extending over the bridge of the nose (they pass in front of the entrance to the nasal passages) and therefore are not very good candidates for commercial use on a conventional "cup-shaped" or "flat-folded" respirator.